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Patients with chronic liver dysfunction and cirrhosis have a hyperdynamic circulation with low peripheral vascular resistance and an increased cardiac index.
Coagulopathies, edema and ascites, renal dysfunction, portopulmonary hypertension, hepatopulmonary syndrome, and autonomic neuropathies are common in patients with liver disease.
The cause of hepatic encephalopathy is believed to be multifactorial. Hepatic encephalopathy resembles and must be differentiated from many other nonfocal neurologic conditions such as hypoglycemia, hyponatremia, intracranial hemorrhage or mass lesions, and meningitis.
Patients scheduled for a hepatic resection should be evaluated as any patient scheduled for major noncardiac surgery. Plans for monitoring, vascular access, induction and maintenance of anesthesia, postoperative pain control, and postoperative care should take into account a large subcostal incision and the potential for sudden massive hemorrhage and severe physiologic derangements during and after surgery.
The most common indication for liver transplantation is chronic hepatocellular disease due to alcohol and/or hepatitis. Hepatitis C is increasingly important, representing a unique and growing health risk for anesthesiologists.
Cardiac assessment of the patient being considered for liver transplantation focuses on functional and invasive tests of cardiac performance that assess ischemic potential and the search for cardiac structural anomalies that might compromise outcome from orthotopic liver transplantation.
Liver transplantation comprises 3 phases. During the preanhepatic phase, a complete hepatectomy is performed. During the anhepatic phase, vascular anastomoses between the donor liver and the recipient's vessels are constructed. During the neohepatic phase, the hepatic arterial and biliary anastomoses are constructed, and the wound is closed.
The 2 common techniques for liver transplantation are the en-bloc technique with interruption of vena caval flow and the piggyback technique with preservation of vena caval flow.
The goals of hemodynamic management are to provide sufficient circulating volume, vascular tone, and cardiac output to perfuse the vital organs. This is not guided by any single parameter but rather by a synthesis of all available data.
The effects of portal hypertension and ascites are alleviated by nonshunting and shunting procedures. Nonshunting procedures are aimed at controlling hemorrhage from portosystemic varices. Shunting procedures redirect the portal venous flow into the systemic venous circulation via a nonvariceal conduit, thus relieving portal hypertension, decompressing varices, and at the same time relieving ascites.
Most livers made available for transplantation come from heart-beating cadaveric donors. When caring for organ donors, the focus of care has shifted from preserving the patient to preserving the function of graft organs. Due to the shortage of cadaveric donors, the use of living donors is growing. In these cases, donor safety is a primary concern, as the donor derives no physical benefit from the surgery.
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Anesthesia for surgery of the hepatobiliary system is a challenging and rapidly evolving subspecialty of anesthesiology. The growth of this subspecialty has paralleled the evolution of hepatic surgery from a risky and heroic enterprise to a more routine undertaking over the past decades. Better understanding of hepatic anatomy, improved diagnostic imaging capabilities, enhanced patient selection and risk stratification, and technical advancements in surgical and ...